Data sets may include data elements that should be hashed to protect the included information. As some examples, personal or confidential information such as customer details, health information, tax identifiers, and social security numbers may be included in fields of a database. Due to the relative uniqueness of many of these types of fields, they may be included in database fields, indexes or table primary keys. As a result, the personal or confidential information fields may be included in the data records for use as unique identifiers rather than for use for the specific information contained within. However, because the design of data tables may depend on these items of personal information, it may be difficult to adequately protect the included confidential information while maintaining data set integrity and utility.